Dental tray



Aug. ll, 1925.

1,549,415? s. R. HANDYSIDE DENTAL TRAY Filed not. 2?-, '1921 ATTf JEY.

Patented Aug. l1, 1925.

u1u-rusa. srafirgsfs .simon ROBERT HANDysrnn, or SAN FRANCISCO,0CALIFORNIA.

DENTAL TRAYJ- l i To' @ZZ/whom it 'may concern.:

Be it known that I, SIMON R. I-IANDYsIm-1, a citizen; `of jthe.UnitedfStates,e.4 residing at San Francisco, in the county of SanFrancisco, State of California, have invented a new and useful DentalTray, of which the following is a specification in such full and clearterms as will enable those skilled in the art to construct and use thesame.

This invention relates to a dental tray and one of its objects is toprovide means to prevent the compound used for taking the impression ofthe mouth from flowing over the back of the tray when the impression isbeing taken.

A further object of the invention is to provide means whereby the depthof the material forming the cast will be prevented from being thinnerthan a predetermined minimum.

A further obj ect of the invention is to pro vide means whereby theimpression made will be suitably lined or grooved in order that it maybe separated into several parts and thereby more easily removed from themouth than it would be if attempted to be removed after the cast hasbeen made in a single piece.

A further object of the invention is to provide the tray with asufficiently resilient bottom to permit it to accommodate itself toirregularities of different mouths, while at the same time maintaining athickness of the cast above the given minimum.

A further object of the invention is to provide a tray with a resilientedge around its outer edges which will aid the operator in producinggood casts by preventing the overflowing of the casting material at theedges of the tray.

Other objects of the invention will appear as the description proceeds.

An embodiment of the invention is shown in the accompanying drawings inwhich the same reference numeral is applied to the same portionthroughout, but I am aware that there may be modifications thereof.

Fig. 1 is a plan view of one form of the tray.

Fig. 2 is a sectional view of the tray.

Fig. 3 is a plan view of an ordinary form of tray with the productionbeads formed therein.

Fig. 4L is a view of the tray shown in Figure 3 looking from the righthand side, and

Fig. y5 .isa sectional viewv ofoneportionof theutray .shownin Figure 3fThetray-has a handle,` 1 and :consists of` a, sheet of thin metal formedto produce a horse-shoe like retaining groove indicated at 2 with araised central portion 3. In the bottom of the tray there is secured abody of suitable resilient rubber 4. This rubber has a horse-shoe likeraised rib 5 extending around its outer portion, a medium raised rib 6and two laterally raised ribs 7 and 8. The rubber body used in t-he formof the invention shown in Fig. 2, is more or less porous spongy rubberin its lower portion, while the upper part is more dense, as indicatedat 9, in that cross-section.

The front and side edges of the tray are provided with a rubber strip 9which is sufficiently resilient to come in contact with the inside ofthe mouth and gums and prevent the loss of the casting material over thetop of the tray, and which forms the surface of the less dense body ofrubber used at the bottom of the tray.

At the back of the tray there is a raised rubber' dam 10 which preventsthe loss of the casting material at the back of the tray.

Vhen a cast is to be made the tray is covered over with a suflicientamount of the casting material and is placed within the mouth of theperson whose impression is to be taken. lhen the tray is pushed upagainst the teeth, the ribs 5, 6, 7 and 8 prevent the teeth fromcuttingy into the impression material deeper than the thickness of saidribs thereby insuring an even depth of casting material all around thetray.

Vhen the material has hardened, the tray may be removed from the cast;whereupon the cast is easily removed from the teeth because it is brokenup by reason of the grooves formed by the ribs 5, 6, 7 and 8 into siXdifferent sections, each section may be easily re-assembled after havingbeen removed from the mouth.

In the form of the invention shown in Figures 3 to 5 inclusive, the trayhandle is indicated at 12, and the tray is of an ordinary form with ahorse-shoe shaped groove 13 to receive the casting material. This groovehas a bead 14 in its bottom and a bead 15 at the front extendingtransversely across the first bead. Rubber dams 16 and 17 are formed atthe back of the horse-shoe shaped groove, and both the front and insideedges of the tra-y are provided with a rubber covering as indicated at18 and 19.

The operation of producing the cast and removing it from the mouth issubstantially the same in the 'form of the invention shown in thesefigures as with the previous orm.

Inorder to aid in holding` the casting material heaped up to lit thecenter of the mouth7 the center` of the tray is slightly roughened asindicated at 6.

What I claim is as follows, but various modifications may be made in theconstruction shown in the drawings and above par- Lin the inal cast.

In testimony whereof I have hereunto set my hand this 20th day ofOctober' A. D. 1921.

SIMON ROBERT HANDYSIDE.

